Author Topic: SCF can't be converged when calculating zero-bias transmission in MTJ device  (Read 2565 times)

0 Members and 1 Guest are viewing this topic.

Offline guyue03

  • Regular QuantumATK user
  • **
  • Posts: 11
  • Country: cn
  • Reputation: 0
    • View Profile
Hi,
  Here is my problem. The  SCF can't be converged when calculating zero-bias transmission in MTJ device by using ATK 17. However, SCF is finished when using ATK 13.
  Could you tell me how to solve this problem? I want to do the calculation with ATK 17. The file is attached.

Thank you so much!

Offline Petr Khomyakov

  • QuantumATK Staff
  • Supreme QuantumATK Wizard
  • *****
  • Posts: 1290
  • Country: dk
  • Reputation: 25
    • View Profile
Take a look at NEGF convergence guide at https://docs.quantumwise.com/technicalnotes/negf_convergence_guide/negf_convergence_guide.html.

You may also try increasing the electrode extensions and reduce damping factor. Another thing is to change Equivalent Bulk, https://docs.quantumwise.com/manual/Types/EquivalentBulk/EquivalentBulk.html, to Neutral Atom, or vice versa to see if that changes the convergence behavior.

It would also be helpful to see your log files for the calculations done with 2013 and 2017 versions. Did you use the same python script for the two calculations.

Offline guyue03

  • Regular QuantumATK user
  • **
  • Posts: 11
  • Country: cn
  • Reputation: 0
    • View Profile
Thank you so much!